<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <form action="/add/" method="get">
        a:<input type="text" name="a"><br>
        b:<input type="text" name="b"><br>
        <input type="submit" value="提交">
    </form>
</body>
</html>